1. Field of Invention
The present disclosure relates in general to a system for coupling annular member to hanger used in a wellhead assembly.
2. Description of Prior Art
Wellheads used in the production of hydrocarbons extracted from subterranean formations typically include a wellhead assembly attached at the upper end of a wellbore formed into a hydrocarbon producing formation. Support hangers for suspending production tubing and casing into the wellbore are generally included within the wellhead assemblies. The casing lines the wellbore and isolates the wellbore from the surrounding formation. The tubing, which typically lies concentric within the casing, provides a conduit therein for producing the hydrocarbons entrained within the formation.
Wellhead assemblies also typically include a wellhead housing and a production tree atop the wellhead housing. Wellhead housings are often adjacent where the casing and tubing enter the wellbore. The production tree is commonly used to control and distribute the fluids produced from the wellbore and selectively provide fluid communication or access to the tubing, casing, and/or annuluses between the tubing and casing. Valves assemblies are typically provided within wellhead production tees for controlling fluid flow across a wellhead, such as production flow from the borehole or circulating fluid flow in and out of a wellhead.
Lockdown rings typically restrain each casing hanger within the wellhead housing to prevent relative axial movement between the casing hanger and wellhead housing. Usually proximate the lockdown rings are return passages that allow fluid flow during cementing operations. The passages typically are bored axially through the casing hangers and are in the form of slots along the inner surface of the wellhead housing.